.alpha.-Amylase enzymes have been used industrially for a number of years and for a variety of different purposes, the most important of which are starch liquefaction, textile desizing, starch modification in the paper and pulp industry, and for brewing and baking. A further use of .alpha.-amylases which is becoming increasingly important is the removal of starchy stains during washing or dishwashing.
As Ca.sup.2+ ions may disturb in industrial applications, Ca.sup.2+ ions are undesired in e.g. laundry and dishwashing detergents, it is the object of the present invention to provide an alkali table amylase which is stable within a broad range of the metal on (e.g. Ca.sup.2+) concentrations.